1. Field
The present disclosure relates generally to depositing material onto substrates and, in particular, to depositing magnetic material onto substrates. Still more particularly, the present disclosure relates to a method and apparatus for atomizing a mixture comprising magnetic particles for an aerosol deposition process.
2. Background
Aerosol deposition may be used in the place of traditional printing techniques. These printing techniques may include, for example, without limitation, screen printing, inkjet printing, and lithography. Aerosol deposition may use an aerosol to “print” one or more layers of material onto a substrate. An aerosol, as used herein, may be a colloid of solid particles or liquid droplets in air or some other type of gas.
With aerosol deposition, the aerosol is sprayed onto the substrate in the form of a focused stream, or jet, of aerosol to deposit the one or more layers of material onto the substrate. Thus, aerosol deposition may also be referred to as aerosol jet deposition. Aerosol deposition may be used to create a variety of objects including, but not limited to, film transistors, resistors, printed circuit boards, and other types of printed electronic devices.
In some cases, the aerosol used in aerosol deposition may be produced by atomizing a solution comprised of a solvent and nanoparticles. As one illustrative example, an ink solution may be atomized to form an aerosol. The ink solution may be comprised of a solvent nanoparticles such as, for example, without limitation, silver nanoparticles, copper nanoparticles, plastic nanoparticles, or some other type of non-magnetic nanoparticles.
Aerosol deposition may allow printing with solutions that are more viscous than is allowed with traditional printing techniques. The solutions used in aerosol deposition may have viscosities up to about 5000 centiPoise (cP). These solutions may typically be comprised of nonmagnetic nanoparticles. A stirrer, typically magnetic, may be used to stir the solution to keep the solution homogeneous such that the aerosol produced is also homogeneous. A homogeneous aerosol may result in a better print quality than a heterogeneous aerosol.
In some cases, it may be desirable to use a solution comprised of magnetic nanoparticles. However, with a solution comprised of magnetic nanoparticles, a magnetic stirrer may be unable to effectively stir the solution to maintain the homogeneity of the solution. The magnetic nanoparticles may stick to and agglomerate around the magnetic stirrer. Thus, some other type of method of maintaining the homogeneity of the solution may be required. Therefore, it would be desirable to have a method and apparatus that take into account at least some of the issues discussed above, as well as other possible issues.